Through a preliminary permit issued on Jan 9, 2013, the Federal Energy Regulatory Commission has granted permission to Corral Creek South Hydro to study the feasibility of developing a 1,100 MW pumped storage project near Twin Falls in Twin Falls County, Idaho.

Corral Creek South Hydro, a subsidiary of Riverbank Power is seeking to construct two earthen dams- one 180-foot-high and 8,400-foot-long and the other 200-foot-high and 4,140-foot-long - to create the upper and lower reservoirs as well as a 10.6-mile-long, 500 kV transmission line. The proposed upper and lower reservoirs would be constructed near China Creek, a tributary to the Salmon Reservoir.

While the permit does not allow any construction activities, the Department of Interior has expressed concern that sensitive fish species, such as redband trout, and other protected wildlife resources could be adversely affected by the project. The Department is also concerned about the potential effects on water quality and quantity.

The same developer has already held a preliminary permit for three years with this new permit also valid for three years.